Current sensors are used for a variety of applications, such as for measuring or detecting how a current splits up if several conductors are connected in a circuit node.
FIG. 28 shows a node connecting three wires (or conductors). This is a common situation in many power distribution systems, where primary energy may be input to the system via I1 (wherein I1 may designate a first current). It may flow to a load via I2 (wherein I2 may designate a second current), but it can also flow to a back-up battery via I3 (wherein I3 may designate a third current). It may also happen that in some instances I1 is equal to zero (I1=0) and the load (I2) is supplied merely by the battery (I3). This situation can also occur in electric vehicles where I1 may be supplied by a charger, I2 is flowing through the electric motor of the vehicle, which can also serve as a means for recuperation of kinetic energy into electric energy, and I3 comes from a large bank of batteries in the vehicle. In such situations it is not only of interest to measure a single current in a single branch of this network, but rather to measure the currents in all branches.